TABLE 7

The ratio of the log KB value for CGP12177 (as an antagonist of cimaterol; thus, at the high affinity conformation) and log EC50 value for CGP12177 (as an agonist of the secondary low affinity conformation) for responses seen at the β1-WT and β1-TM4 chimeric receptors (data taken from Table 6)

Ratio of the affinity for antagonists at the two conformations is given (i.e., log KB for antagonism of cimaterol at high affinity site/log KB for antagonism of CGP12177 at low-affinity site). This table examines the ratio of the affinities of ligands and shows that the ratio of affinities between the two conformations is much less for β1-TM4 stage 5 and beyond, suggesting that only the amino acids in stage 5 and beyond are important for the secondary conformation.

Ratio of Log KB CGP12177/Log EC50 CGP12177Ratio of Log KB (Cimaterol as Agonist)/Log KB (CGP12177 as Agonist)
CGP20712AICI118551Propranolol
β1-WT1.891.991.272.00
β1-TM4 stage 11.531.780.832.47
β1-TM4 stage 21.351.791.062.01
β1-TM4 stage 31.451.821.101.75
β1-TM4 stage 41.841.881.051.61
β1-TM4 stage 50.640.230.170.63
β1-TM40.550.450.300.69